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51.
S. Lal R. Raghavan T. N. Rangaswamy B. V. Sreekantan A. Subramanian S. D. Verma S. C. Tonwar R. H. Vatcha 《Proceedings Mathematical Sciences》1971,73(4):170-178
Detailed features of extremely collimated nuclear interactions induced by cosmic ray particles in carbon and brass (belonging to group I as classified in Part I of this series of papers) are presented. These extremely collimated nuclear interactions seem to be preferentially induced by pions rather than by nucleons; also the relative frequency of these seems to be less when brass is used as target compared to the case with carbon as target. The distribution of multiplicities of secondary particles emitted in the forward direction show certain regularities in the case of interactions induced by charged primaries. Observations on the γ-rays associated with these events give support to the interpretation that in these inelastic collisions pions are produced in pairs in the forward direction with low transverse momentum. It is suggested that such a low energy di-pion system could be the same as found in the so-called ABC effect. 相似文献
52.
When sound waves of high amplitude propagate, several non-linear effects occur. Ultrasonic studies in liquid mixtures provide
valuable information about structure and interaction in such systems. The present investigation comprises of theoretical evaluation
of the acoustic non-linearity parameter B/A of four binary liquid mixtures using Tong and Dong equation at high pressures and T=303.15 K. Thermodynamic method has also been used to calculate the non-linearity parameter after making certain approximations. 相似文献
53.
Lal Sohan Arora Sanjiv Kumar Vinod Rani Shikha Sharma Chetan Kumar Parvin 《Journal of Thermal Analysis and Calorimetry》2018,132(3):1707-1716
Journal of Thermal Analysis and Calorimetry - The synthesis of Schiff bases of chitosan is performed by the reaction of chitosan with different heteroaryl aldehydes, i.e., furfuraldehyde,... 相似文献
54.
Dwivedi Jyotsana Gupta Abhishek Verma Shikhar Paliwal Sarvesh Rawat Ajay Kumar Singh 《平面色谱法杂志一现代薄层色谱法》2019,32(2):103-108
JPC – Journal of Planar Chromatography – Modern TLC - A high-performance thin-layer chromatography (HPTLC) method for the simultaneous quantitative determination and validation of... 相似文献
55.
Savita Verma Deepak M. Maher Samadhan S. Nagane Bhausaheb V. Tawade Prakash P. Wadgaonkar 《Journal of polymer science. Part A, Polymer chemistry》2019,57(5):588-597
New aromatic (co)polyesters containing pendant propargyloxy groups were synthesized by phase transfer‐catalyzed interfacial polycondensation of 5‐(propargyloxy)isophthaloyl chloride (P‐IPC) and various compositions of P‐IPC and isophthaloyl chloride with bisphenol A. FTIR and NMR spectroscopic data, respectively, revealed successful incorporation of pendant propargyloxy groups into (co)polyesters and formation of (co)polyesters with desired compositions. (Co)polyesters exhibited good solubility in common organic solvents such as chloroform, dichloromethane, and tetrahydrofuran and could be cast into transparent, flexible, and tough films from chloroform solution. Inherent viscosities and number average molecular weights of (co)polyesters were in the range 0.77–1.33 dL/g and 43,600–118,000 g/mol, respectively, indicating the achievement of reasonably high‐molecular weights. The 10% weight loss temperatures of (co)polyesters were in the range 390–420 °C, demonstrating their good thermal stability. (Co)polyesters exhibited Tg in the range 146–170 °C and Tg values decreased with increase in mol % incorporation of P‐IPC. The study of non‐isothermal curing by DSC indicated thermal crosslinking of (co)polyesters via propargyloxy groups. The utility of pendant propargyloxy group was demonstrated by post‐modification of the selected copolyester with 1‐(4‐azidobutyl)pyrene, 9‐(azidomethyl)anthracene, and azido‐terminated poly(ethyleneglycol) monomethyl ether via copper(I)‐catalyzed Huisgen 1,3‐dipolar cycloaddition reaction. FTIR and 1H NMR spectra confirmed that click reaction was quantitative. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 588–597 相似文献
56.
Kapil Mohan Saini Rakesh K. Saunthwal Sushmita Akhilesh K. Verma 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(5):1017-1021
Transition-metal-free regioselective synthesis of functionalized amino-indenones by the reaction of ortho-alkynylaldehydes with a broad range of primary amines by intramolecular cyclization has been described. The designed reaction proceeds through KOH-mediated Prins-type cyclization and DMSO-promoted oxidation of the cyclopent-2-en-1-one system. The proposed mechanism and role of solvent were well supported by control experiments. For the first time, we have disclosed the reverse reactivity of (2-alkynyl)-arylaldimines in a super basic system. 相似文献
57.
In this paper we present an expression relating the lattice thermal expansion coefficient αL (10−6 K−1) for the AIIIBV and AIIBVI semiconductors with the product of ionic charges (Z1Z2), melting temperature (Tm) and nearest neighbor distance d (Å). The lattice thermal expansion coefficient of these compounds exhibit a linear relationship when plotted on a log–log scale against the melting temperature (Tm), but fall on different straight lines according to the ionic charge product of the compounds. A good agreement has been found between the experimental and calculated values of the lattice thermal expansion coefficient for AIIIBV and AIIBVI semiconductors. 相似文献
58.
In this paper, we introduce fuzzy mathematical programming (FMP) for decision-making related to software creation by selecting
optimal commercial-off-the-shelf (COTS) products in a modular software system. Each module in such software systems have different
alternatives with variations in their properties, for example, quality, reliability, execution time, size and cost. Due to
these variations, component-based software developers generally deals with the problem of selecting appropriate COTS products.
The development of COTS-based systems largely depends on the success of the selection process. Various crisp optimization
models of COTS products selection have been proposed in literature. However, in real COTS products selection problem, it is
difficult to estimate precisely the values of various model parameters due to lack of sufficient data and also because of
measurement errors. Hence, instead of crisp optimization model, if we use flexible optimization model then we might obtain
results which are more preferred by the decision maker. In this study, we use multiple methodologies such as quality model,
analytical hierarchy process and FMP to develop fuzzy multiobjective optimization model of the COTS products selection. To
determine a preferred compromise solution for the multiobjective optimization problem, an interactive fuzzy approach is used. 相似文献
59.
Jyoti Bhawan Singh Shakti Pratap Gupta Mohit Tripathi Sudhanshu Verma Alok Kumar Singh Devraj Yadav R. R. 《Acoustical Physics》2021,67(6):584-589
Acoustical Physics - We have estimated elastic, mechanical, thermal and ultrasonic properties, in high temperature regime, of cobalt nanowires (Co-NWs) having a hexagonal close-packed (HCP)... 相似文献
60.
Ram U. Verma 《Rendiconti del Circolo Matematico di Palermo》1999,48(2):201-208
The solvability of a class of generalized strongly nonlinear variational inequality problems on nonempty closed convex sets
in Hilbert spaces is presented. 相似文献